1. Technical Field
The present invention relates to a liquid ejecting head, a liquid ejecting head unit, and a liquid ejecting apparatus that eject a liquid through a nozzle opening, and more particularly to an ink jet recording head, an ink jet recording head unit, and an ink jet recording apparatus that dispense ink as an example of the liquid.
2. Related Art
Some of currently available ink jet recording heads, examples of the liquid ejecting head, include an actuator unit that includes a piezoelectric element and a pressure chamber, and a flow path unit that includes a nozzle plate with nozzle orifices communicating with a pressure chamber for dispensing ink and a manifold plate including a manifold that serves as a common ink chamber of the pressure chamber.
With reference to such ink jet recording heads, for example JP-A-2006-95725 proposes sealing the manifold with the nozzle plate and utilizing the portion of the nozzle plate sealing the manifold as a compliance portion that can be deformed by pressure fluctuation inside the manifold.
Also, for example JP-A-2009-208461 proposes providing a compliance plate that includes the compliance portion that can be deformed by pressure fluctuation inside the manifold, on a bottom face of the manifold plate.
In the latter case, the compliance plate includes a recess where the thickness of the compliance plate is reduced, and such a recess serves as the compliance portion.
However, in the case where the compliance portion is formed on the nozzle plate as JP-A-2006-95725, vibration of the compliance portion directly propagates to the vicinity of the nozzle orifice, thereby affecting the dispensing direction or dispensing characteristic of the recording head. Also, the nozzle plate cannot be made thinner because the nozzle orifices have to be formed therethrough, while it is preferable to make the compliance plate thinner in order to secure flexibility of the compliance portion. Thus, it is difficult to sufficiently realize both the function of a nozzle plate and the function of a compliance plate, with a single substrate.
Also, sufficient space that allows deformation of the compliance portion cannot be secured by simply forming the recess on the compliance plate as the compliance portion as JP-A-2009-208461, and hence the compliance portion cannot fully absorb the pressure fluctuation inside the manifold, which results in a degraded ink dispensing characteristic. The compliance plate has to have a certain thickness for forming the recess, and hence a communication channel (flow path) from the pressure chamber to the nozzle orifice becomes long, which makes the ink dispensing characteristic disadvantageous for high-frequency driving.